Table 2. Consensus Statement on Tremor by the Movement Disorder Society. Criteria for Orthostatic Tremor.

Orthostatic tremor is a unique tremor syndrome characterized by:

1. A subjective feeling of unsteadiness during stance but only in severe cases during gait; patients rarely fall. None of the patients have problems when sitting and lying.

2. Sparse clinical findings that are mostly limited to a visible and occasionally, only palpable fine amplitude rippling of the leg (quadriceps or gastrocnemius) muscles when standing.

3. The diagnosis that can be confirmed only by electromyography recordings (e.g. from the quadriceps muscle) with a typical 13–18 Hz pattern. All of the leg, trunk, and even arm muscles can show this tremor, which is typically absent during tonic activation while the patient is sitting and lying.